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Introduction (for those new to this website):
Tamara Rubin is a multiple-federal-award-winning independent advocate for consumer goods safety and a documentary filmmaker. She is also a mother of Lead-poisoned children (her sons were acutely Lead-poisoned in 2005). Since 2009, Tamara has been using XRF testing (a scientific method used by the U.S. Consumer Product Safety Commission) to test consumer goods for toxicants (specifically heavy metals — including Lead, Cadmium, Mercury, Antimony, and Arsenic). All test results reported on this website are science-based, accurate, and replicable. Items are tested multiple times to confirm the test results for each component tested. Tamara’s work was featured in Consumer Reports Magazine in February of 2023 (March 2023 print edition).
Published: Friday — June 16, 2023
“What is clearance testing?”
“What is a dust wipe sample?”
“How do you collect a Lead Dust Sample?”
(Always get clearance testing done before moving into your home and after any renovations.)
I have written this article so that families working on their home (renovating, repairing, or painting) can better understand the testing that needs to be done before they move back into the home (after their work is done), ensuring it is safe for their family’s return. Unfortunately, the EPA “RRP” Rule legislation (which was ostensibly designed to help protect families from exposure to Lead dust created as a result of Renovation, Repairs, or Painting) falls significantly short of its intended goal to protect families. This article is only about clearance testing (a practice expressly and intentionally NOT included in the EPA RRP Rule, even though it should have been)! For many of the other ways the EPA RRP Rule falls short of its intended goal of protecting families, please watch the documentary film I directed and produced — MisLEAD: America’s Secret Epidemic (linked here).
Section #1) First: “What is ‘Dust Wipe Sampling’?”
“What does a ‘Lead Dust Wipe Test’ look like/ how does that work?”
You can see several examples of the dust wipe sampling process (completed by me, my son, and my husband) on the Lead Safe Mama YouTube channel. Here are some links:
- Dust wipe sampling for Lead on the floor (known to be likely Lead-contaminated)
- Dust wipe sampling for Lead on a Tempur-Pedic mattress
- Dust wipe sampling for Lead on a vintage book (after testing positive with an XRF instrument)
Dust wipe sampling for Lead entails the following steps:
- Purchase a Lead dust sample kit (or the tools included in the kit).
- Carefully mark off the specified square-footage area (usually one square foot, or sometimes two square feet).
- Use the “ghost wipe” (it looks similar to a little moist hand-wipe that comes in a sterilized packet) to wipe the pre-marked-off surface thoroughly, using the technique shown in my videos (and described in the instructions that come with the kits).
- Place the wipe in a sterile container (plastic test tube-like container or a new plastic baggie) that is marked on the outside with the location where the sample was taken (like “center of kitchen floor” or “under back bedroom south corner window”).
- Fill out the “chain of custody” paperwork required by the lab (instructions for this are included in the kit).
- Send the sample to a lab to determine how many micrograms of Lead are in the dust that was collected on the sample (ghost wipe).
- Now, just wait for the lab to analyze the sample (usually five days from when they receive it) and e-mail you a report with the test results for the samples you sent in.
You can also hire an independent contractor to conduct the dust wipe sampling for you. This type of contractor is generally called a Hazard Assessor (or Risk Assessor); if you hire a Hazard Assessor to conduct the testing, they will collect the samples and send them to a lab for you.
Dust wipe sampling is the most specific and accurate method of testing for (and confirming or eliminating the concern of) Lead dust that may be in a home or other environment. Given the fact that it takes a literally invisible amount of micro-particulate Lead in house dust to poison a child (read more about that here), dust wipe sampling is actually the only way to definitively quantify/evaluate the level of risk for Lead exposure to humans in a specific home. (It is more specific and accurate than any type of visual inspection or XRF testing.)
The EPA RRP Rule includes a “cleaning verification card” requirement — which was integrated into the regulation as a concession to contractors (so they ostensibly “would not need” to do clearance testing). This requirement does not provide any safety measures for families and instead provides a false sense of security. The so-called “cleaning verification card” method for determining if a house is safe for a family to return to after renovative work should NEVER be used and was only implemented for the benefit of contractors — not families. I will discuss that more in detail in an upcoming separate article and will link that article here when it has been published.
Section #2) What is “Clearance Testing” for Lead, specifically?
Clearance testing for Lead is when you do a group of dust wipe samples (see section #1 above) to determine if a home is safe to live in. When you complete a clearance testing (or have clearance testing conducted for you) there are two possible outcomes: 1) the home PASSES or 2) the home FAILS.
Unfortunately, many people simply assume (too often, falsely) that their home is safe to live in right after the clearance testing is done. They don’t make the time in their renovation plan to wait for test results to come back from the lab before moving back into their home after the work is completed. This ROUTINELY results in Lead-poisoned children. (The first round of clearance testing OFTEN reveals residual Lead hazards due to unsafe work practices, inadequate containment, and/or insufficient post-work clean-up. Please read the sections below for details about this — with examples!)
You should always include extra time in your plan for living in alternate housing after completing your renovation or repainting work on pre-1978 homes (two weeks to a month should do, depending on whether or not your budget allows for expediting the test results). This window allows enough time for you to wait for test results to come back from the lab, as well as enough time to accommodate for the possibility of the first set of results coming back as “FAILED” — which will require you do a full abatement-level round of cleaning on the home. Then, re-testing and waiting for a subsequent separate round of testing results to come back with (hopefully) a “PASS.”
You should not consider your home to have passed clearance testing until ALL dust wipe samples have come back with results that are “less than 5 micrograms of Lead in dust per square foot tested.” (<5)*
*The current federal standard for determining if a home “passes clearance” is that dust wipe samples done on horizontal surfaces (like floors) must come in at levels below 10 micrograms of Lead per square foot. This is a level that is not protective of human health. While the federal hazard level was originally set at 40 micrograms of Lead per square foot and was recently lowered to 10 micrograms, the scientific recommendation back in the early 1990s, when the hazard level was first set, was a level actually determined to be protective of human health. This recommendation was that dust wipe samples should fall below 5 micrograms per square foot for a home to pass clearance. It is for this reason that Lead Safe Mama, LLC supports the need for levels to be below 5 micrograms to pass clearance.
Section #3) “Where should I test when doing clearance testing?”
When conducting clearance testing (either after work has wrapped up on a property OR before you move into a newly-purchased, newly-rented-but-recently-renovated property) you should test as many spots as possible. For a 2,000-square-foot home, 10 samples might give you a good idea of potential hazards, but 20 or 30 samples would represent a more comprehensive and better health protective effort. Here’s a list of where you might want to test, in the order of priorities, with some areas specifically chosen because if they test positive for a high level of Lead, it is highly likely that sufficient post-work cleaning was not done:
- Under radiators (if present)
- Under or behind the fridge
- Under or behind the washer/dryer
- No furniture should remain in a home when Lead paint work is done, but if the furniture was left in the home, under beds
- Center of children’s bedroom floor
- Corner of the child’s bedroom
- Closet of child’s bedroom
- Under the window sill (on the floor) of the child’s bedroom
- Window sill (interior) of child’s bedroom
- Window well of child’s bedroom (the dip in the frame that is exposed when the window is lifted)
- Exterior window sill of windows in the child’s bedroom (if this has a high level of Lead in the dust, it is dust that tends to migrate into the child’s room if not taken care of)
- Center of child’s playroom
- Corner of child’s playroom
- One or more samples should be done on the inside of any forced-air heating registers — intake and outflow (both active and/or inactive legacy registers) — NOTE: these systems should always be fully sealed off BEFORE any work is done
- Several spots on any carpeted areas — NOTE: carpet should never be in homes where there are active or likely Lead-hazards, and carpet should never be left in a home when renovations or repainting are being done, however, if the carpet was in the home during renovations and if it is not possible for you to remove it (perhaps because you are a tenant), you must test a few spots on any of the carpeted areas. Please click this link to read more about safely removing Lead-contaminated carpets — link is not yet live, stand by
- Corner (an area most likely to collect dust) in the dining room
- Corner (an area most likely to collect dust) in the living room
- Corner (an area most likely to collect dust) in any other room
- Outside the front door on the threshold (porch or stoop)
- Inside the front door on the threshold (the area that the door swings over when it opens and closes)
- Driveway (click here to read more about cleaning concrete)
- The path up to your home (and any other paths that were used by anyone involved in the execution or clean-up — such as a patio or concrete section used as the crew’s temporary “toolbox, equipment, or materials-storage depot,” etc.)
- Back porch
This list is not fully exhaustive. Separately (depending on the circumstances), one might want to take dust wipe samplings in the rain gutters of a home and on the exterior siding. Soil testing should always be done if soil contamination is suspected as well. Soil testing is discussed separately in the article linked here.
Section #4) “When should Clearance Testing for Lead be conducted?”
Clearance testing should occur at the following times:
- When you first purchase a pre-1978 home (or a home in a densely populated urban environment, regardless of the age of the home), but before you move in. Ideally, you need to make sure the home passes clearance before you move in. It can take one to two weeks to get your test results back from the lab, so it is good to plan on living elsewhere for at least two weeks before you move into the home. Planning at least a month of alternate housing after you close escrow will give you the opportunity to deal with any issues if necessary, and to do appropriate cleaning and follow-up testing (ensuring the home passes clearance before you move in). For example, we closed escrow on our home in early February but did not move in until mid-April. We used that time (during which we continued to live in the house we had been renting) for several rounds of testing, as well as a bunch of (subsequent) Lead-hazard remediation work (including window replacement) in response to the testing we had finished.
- When the contractor has completed a job (especially any large jobs for which you moved out of the home). This follows the same timeline as noted in #1 above.*
- Before you move into a home you have rented, ESPECIALLY if you have children and if any of the following applies: if you live in a city/urban area, if the landlord has told you they recently did renovations if you have known contaminated soil in your area, and if you are planning on living in the rented home for an extended period of time (longer than a year).
* NOTE: you should NEVER live in a home while work is being done if the home was built before 1978, or if the work includes tile demolition or installation (regardless of the home’s age) with tiles from any era (including modern tiles made and installed today).
Section #5) “Who should do the Clearance testing?”
You can do clearance testing yourself, or you can hire a contractor to do clearance testing. If your child has been poisoned, your county health department may also offer to do clearance testing for you — free of charge. Here are some important points to consider:
- You should NEVER let the contractor who did the work on your home hire a company to do clearance testing for their job, as this constitutes an inherent conflict of interest.
- You should NEVER ask your contractor for a referral to a company that does clearance testing — this also represents an inherent conflict of interest.
- You should NEVER trust a clearance test provided by a landlord or seller of a home. It is too easy for them to hire a contractor and skew/ “doctor” the test by only testing a few areas that were thoroughly cleaned the day the testing was done, rather than testing all potential problem areas.
- This issue is discussed in my film … In upstate New York, there is a common practice where Section 8 landlords open the windows of their homes and then do a thorough cleaning of the home; they leave the windows open and perform the clearance testing (which — under these contrived optimized conditions — “passes”). But the minute the landlord closes the windows after the Hazard Assessor has been there, there is a shower of Lead dust created by the friction of the function of the window, and the area is immediately contaminated.
- If the health department does work on your home (through the federally-funded Lead Hazard Remediation grant program), you should ask if you can choose the Hazard Assessor that will conduct the clearance testing on the job. If they do not let you choose the Hazard Assessor/contractor, this represents an inherent conflict of interest. (Recently, people have shared personal stories with me of county-hired Hazard Assessors “passing” homes that should not have passed clearance, simply to keep up with their workload!)
- To find an independent contractor that does clearance testing in your area, look on your regional EPA website. If you cannot find a contractor there (they are called Hazard Assessors) you can look on Angie’s List, or join our Facebook group and ask if anyone in the group has hired a reputable/high-integrity Hazard Assessor in your area.
- It is easy (and faster and cheaper) if you do the dust wipe samples yourself. We have some videos on our YouTube channel — linked above — showing you how to collect a dust wipe sample.
Section #6) A little “cheat” we here at Lead Safe Mama, LLC recommend
We have a little “cheat” of the system that we have been recommending for 10+ years. This is a way of collecting a dust sample that is “off-label” to some degree but helps families get more accurate test results from their dust wipe samples than they might normally. Here are the considerations and steps related to that:
- Dust wipe samples are typically done with a one-square-foot area being tested.
- The low threshold of detection for most dust wipe sampling labs is 5 micrograms of Lead per square foot.
- Instead, you can mark off and test TWO square feet for your sample.
- When you send this in — if your level is very low they may give you a test result of (for example) 7 micrograms of Lead dust for the sample.
- You can then divide that in half and know that not only is your sample “less than 5” micrograms of Lead per square foot, but — in fact — it is 3.5 micrograms per square foot.
- This method helps you get down to a low threshold of detection of 2.5 micrograms per square foot.
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Additional Reading That may be of Interest
- An overview article on home inspections/home testing
- The booklet landlords are required to give to tenants BEFORE they sign their lease
- What to expect when the inspector comes (read this before your home inspections)
- Tamara’s advice to one of her best friends buying a home (video)
- The documentary feature film I directed and produced